列表框显示类名而不是值

Question

I'm working on a project where the user is able to create different animals. This is how the inheritance work:

Animal class is the parent for all classes.

Mammal class inherit from Animal class.

Dog class inherit from Mammal class.

Cat class inherit from Mammal class

Reptile class inherit from Animal class

Snake class inherit from Reptile class

Lizard class inherit from Reptile class

The user is able to choose what animal to create. There is one listbox showing the type of animal ( Mammal and Reptile ) and there is a listbox next to it that that depending on the type of animal selected by the user, it displays its animals.

For exampel, if the user selects Mammal in the listbox, the listbox next to it displays Dog and Cat .

The user is then able to select the animal to create and then input some information about that animal and create it to make it show on a result listbox.

I also want it to show a food schedule when an animal is selected on the result listbox. For example if a user selects a dog(after creating it) on the result listbox, the dog's food schedule is to be displayed on a schedule listbox.

The problem is that when I try to select an item on that listbox, the only thing adding to the schedule listbox is class name FoodSchedule

Assign.FoodSchedule

Here are my classes:

There is a FoodSchedule class that works as a class manager.

public class FoodSchedule
    {
       private List<string> foodDescriptionList;

       public FoodSchedule()
       {
           foodDescriptionList = new List<string>();
       }
        public int Count
        {
            get
            {
                if ((foodDescriptionList != null))
                {
                    return foodDescriptionList.Count;
                }
                else
                {
                    return 0;
                }
            }
        }

        public void AddScheduleItem(string item)
        {

            foodDescriptionList.Add(item);
        }


        public string GetFoodSchedule(int index)
        {
           if(ValidateIndex(index))
           {
                return foodDescriptionList[index];
           }
           else
           {
               return null;
           }
        }

        public bool ValidateIndex(int index)
        {
            return ((index >= 0) && (index < foodDescriptionList.Count));
        }

    }
}

The instance variable foodDescriptionList is a collection of string elements where each element is a line of text that describes a part of the feeding schedule.

The info about the schedule is to be contained and filled in an instance of FoodSchedule in for example the Dog class (hard-coded, through an overridden method)

class Dog : Mammal
    {
        private FoodSchedule foodScedule = new FoodSchedule();


public override FoodSchedule FoodDescription
        {
            get
            {
                return this.foodScedule;
            }
        }
public override string GetSpecies()
        {
            return "Dog";
        }

     public override FoodSchedule GetFoodSchedule()
        {

            foodScedule.AddScheduleItem("Some text");


            return foodScedule;
        }

My mainForm :

 public partial class MainForm : Form
    {  
        private FoodSchedule m_foodManager = new FoodSchedule();
        private Dog m_dog = new Dog();
  FoodSchedule animal = m_dog.GetFoodSchedule();

                   if (animal != null)
             {
                    //Adds to the list.
                 foodlst.Items.Add(animal.ToString()); //foodlst is the schedule listbox  
              }    
                foodlst.DisplayMember = "FoodDescription";

Answer 1

From your question, I gather that you want to display the food description (list of string) for the selected animal ie Dog

To achieve this in your FoodSchedule class add a property

public List<string> FoodDescriptionList 
{
     get
     {
          return foodDescriptionList;
      }
 }

And in your main form you can bind this collection to your listbox

if (animal != null)
{
    //Adds to the list.
    foodlst.DataSource = animal.FoodDescriptionList;
}